Multiple cores are used in a nuclear power station, a thermal power station, a control center, a data center, a huge building and others, and the disconnection and the reconnection of a core are ordinarily performed for regular maintenance, the repair, the dismantlement and the installation of a device and others.
As such work has intricate and individual specifications, it has to depend on individual human power and is exposed to a risk of a human error. Strict countermeasures for preventing a human error have been taken using plural check systems; however, even if considerable man-hours are expended for the countermeasures, the countermeasures are not complete.
For this type of core check technique, there are known technique that identification data at a transmitting end is transmitted via a core after the connection of the core and the received identification data and stored identification data at a receiving end are compared (for example, refer to Japanese Unexamined Patent Application Publication No. 2000-338160), technique that the conduction of each conductor is checked by applying a separate identifying signal to each conductor of plural cores and detecting the identifying signal at the other end (for example, refer to Japanese Unexamined Patent Application Publication No. Hei5 (1993)-180892) and technique that an IC tag is attached to both ends of a core, both identification information is compared at the other end and it is discriminated whether both identification information is that of the same core or not (for example, refer to Japanese Unexamined Patent Application Publication No. 2006-243834).